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United States Patent | 6,040,113 |
Van Damme ,   et al. | March 21, 2000 |
Heat-sensitive imaging element for making positive working printing plates according to the present invention there is provided a heat-sensitive imaging element for making positive working lithographic printing plates comprising on a lithographic base a layer comprising a polymer, soluble in an aqueous alkaline solution and an IR-radiation sensitive top layer. Upon image-wise exposure the capacity of the aqueous alkaline solution to penetrate and/or solubilize the top layer is changed. Image-wise exposure can be performed with an infrared laser with a short as well as with a long pixel well time. The obtained positive working printing plates have excellent printing properties and an improved infrared sensitivity.
Inventors: | Van Damme; Marc (Heverlee, BE); Vermeersch; Joan (Deinze, BE) |
Assignee: | AGFA-Gevaert, N.V. (Mortsel, BE) |
Appl. No.: | 025341 |
Filed: | February 18, 1998 |
Current U.S. Class: | 430/271.1; 430/302; 430/911; 430/926; 430/944 |
Intern'l Class: | G03F 007/00 |
Field of Search: | 430/271.1,911,926,944,302 |
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